Oil-water double-cooling electric drive assembly, and new energy automobile

ABSTRACT

An electric drive assembly with oil/water dual cooling is provided that includes a motor module, a gearbox module, a water cooling module and an oil cooling module. Lubricating oil is introduced into the front and rear windings of the motor through three oil conveying passages to improve the cooling performance of the motor. Moreover, the gearbox cavity and the motor cavity do not need to be sealed, which avoids the use of high-speed oil seal of motor shaft, and thus the cost of the drive assembly is reduced and the transmission efficiency is improved. The cooling fluid of the motor cools the lubricating oil through the heat exchanger of the gearbox, thereby solving the heat dissipation problem when the gearbox of the new energy vehicle operates at high speed constantly, and thus improving the service life and reliability of the gear and bearing.

TECHNICAL FIELD

The present disclosure relates to the field of drive assemblymanufacturing, in particular to an electric drive assembly withoil/water dual cooling and a new energy vehicle.

BACKGROUND

As the problems such as oil shortage, air pollution and national energysecurity become getting worse, the new energy vehicle industry isdeveloping rapidly. As one of the core parts of new energy vehicles, themotor gearbox drive assembly has an important impact on the layout ofnew energy vehicle industry. The motor gearbox drive assembly of newenergy vehicle has the characteristics of high rotation speed and highpower density, and has high requirements for reliability, cooling andlubrication. At present, the cooling of motor mainly depends on thecirculating cooling fluid in the water jacket to cool the stator, whilethe cooling of windings depends on natural heat dissipation and withoutbeing directly cooled, so the motor cannot run for a long time atmaximum power. At present, the cooling of the gearbox depends on aircooling, and the cooling effect is poor. Especially in the high rotationspeed range, the temperature rises very fast, which tend to cause theearly failure of internal parts.

At the same time, the end customers' requirements for the mileage andperformance of the whole vehicle become increasingly higher, and theelectric drive system is required to have good power performance andsmoothness. When the torque density is improved, it is urgent to designa set of efficient cooling system to meet the development needs of themarket.

SUMMARY

In view of the above problems, the present disclosure is proposed toprovide an electric drive assembly with oil/water dual cooling and a newenergy vehicle that solve or at least partially solve the abovetechnical problems.

In order to achieve the above object, the present disclosure adopts thefollowing technical solutions.

An aspect of the present disclosure provides an electric drive assemblywith oil/water dual cooling, wherein

the electric drive assembly comprises a motor module, a gearbox module,a water cooling module and an oil cooling module;

the motor module comprises a motor housing, a motor shaft and a stator;

the gearbox module comprises a gearbox housing, and the gearbox housingis connected with a rear end of the motor housing;

the water cooling module comprises a motor water jacket and a heatexchanger, the motor water jacket is integrally cast with the motorhousing, the motor water jacket is provided with a first water inlet anda first water outlet, the heat exchanger is disposed at a lower end ofthe gearbox housing, and the heat exchanger is provided with a secondwater inlet and a second water outlet;

the oil cooling module comprises an oil conveying device, an oilconveying passage and an oil return passage, the oil conveying device isdisposed at a bottom of the gearbox housing, the oil conveying passageis communicated with an inside of the motor housing and an inside of thegearbox housing, and the oil return passage is disposed at a bottom ofthe motor housing.

Optionally, the oil conveying device is one or more gears, and/or theoil conveying device is one or more nozzles.

Optionally, the oil conveying passage comprises a first oil conveyingpassage, and the first oil conveying passage comprises a first oilstorage tank, a first oil inlet, a first oil passage and a first oiloutlet; the first oil inlet is disposed on an upper part of a front endface of the gearbox housing above the motor housing, the first oilstorage tank is disposed below the first oil inlet, the first oilpassage is an oil pipe or is cast integrally with the motor waterjacket, the first oil passage is provided with a first oil outlet at afront end of an upper part of the motor housing, and the first oiloutlet is positioned facing a front winding of the stator.

Optionally, the oil conveying passage comprises a second oil conveyingpassage, and the second oil conveying passage comprises a second oilstorage tank, a second oil inlet, a second oil passage and a second oiloutlet; the second oil inlet is disposed at a position on the front endface of the gearbox housing above the motor housing that is close to themotor housing, the second oil storage tank is disposed below the secondoil inlet, the second oil passage is an oil pipe or is formed by castingat an intersection of a front end of the gearbox housing and an upperpart of the motor housing, the second oil outlet is disposed at a rearend of the upper part of the motor housing, and the second oil outlet ispositioned facing a rear winding of the motor stator.

Optionally, the oil conveying passage comprises a third oil conveyingpassage, and the third oil conveying passage is an oil passage formed bya rear end bearing of the motor shaft.

Optionally, a strong magnetic body is provided at any one or more amongan oil inlet of the oil conveying passage, the bottom of the gearboxhousing and a front side of a rear end bearing of the motor shaftrespectively.

Optionally, the water cooling assembly further comprises a water pipe,and the first water outlet and the second water inlet are communicatedthrough the water pipe.

Optionally, a second water passage and a third water passage are furtherformed by casting in a housing between the motor water jacket and theheat exchanger, the second water passage is hermetically connected orintegrally formed with the second water inlet, and the third waterpassage is hermetically connected or integrally formed with the secondwater outlet.

Optionally, the heat exchanger and the gearbox housing are integrallycast, or the heat exchanger is installed at the bottom of the gearboxhousing.

Another aspect of the present disclosure provides a new energy vehiclecomprising any one of the electric drive assemblies with oil/water dualcooling as stated above.

The motor gearbox drive assembly using the above oil cooling system andwater cooling system has the following advantages:

The electric drive assembly of the present disclosure eliminates theneed for the high-speed oil seal on the motor shaft, reduces the numberof parts, reduces the cost, avoids the friction loss of the oil seal andimproves the efficiency of the assembly.

The oil cooling module in the present disclosure introduces thelubricating oil in the gearbox to the front and rear windings of themotor through multiple passages, so that the temperature of motorwindings is reduced and they can run for a long time under the maximumpower.

The water cooling module in the present disclosure introduces the motorstator cooling fluid into the heat sink of the gearbox to cool thelubricating oil of the gearbox, so as to ensure that the gearbox hasgood heat dissipation performance under a high speed.

The above is only an overview of the technical solutions of the presentdisclosure. In order to better understand the technical means of thepresent disclosure so that it can be implemented according to thecontents of the description, and in order to make the above and otherobjects, features and advantages of the present disclosure more obviousand easy to understand, the specific embodiments of the presentdisclosure are given below.

BRIEF DESCRIPTION OF DRAWINGS

By reading the detailed description of the preferred embodiments below,various other advantages and benefits will become clear to a person ofordinary skill in the art. The drawings are only used for the purpose ofillustrating the preferred embodiments, and should not be considered asa limitation to the present disclosure. Moreover, throughout thedrawings, like reference numerals denote like components. In thedrawings:

FIG. 1 is a schematic view of the structure of an oil/water dual coolingelectric drive assembly in an embodiment of the present disclosure;

FIG. 2 is a sectional view along line A-A in FIG. 1; and

FIG. 3 is a perspective view of an electric drive assembly withoil/water dual cooling in an embodiment of the present disclosure.

In the drawings: 1. gearbox housing, 2. oil conveying device, 3. heatexchanger, 4. second water outlet, 5. intermediate bearing, 6. secondoil passage, 7. strong magnetic body, 8. strong magnetic body, 9. rearwinding, 10. first water inlet, 11. first oil passage, 12. motor waterjacket, 13. front winding, 14. stator, 15. rotor, 16. oil returnpassage, 17. oil return passage port, 18. water pipe, 19. second waterinlet, 20. strong magnetic body, 21. first oil storage tank, 22. secondoil storage tank.

DETAILED DESCRIPTION

Illustrative embodiments of the present disclosure will be described inmore detail with reference to the drawings. Although the drawings showthe illustrative embodiments of the present disclosure, it should beunderstood that the present disclosure can be implemented in variousways and should not be limited by the embodiments disclosed herein. Onthe contrary, the embodiments are provided for a more thorough andcomplete understanding of the present disclosure, so as to fully conveythe scope of the present disclosure to those skilled in the art.

In order to more clearly describe the technical solutions of the presentdisclosure, it is specially specified that in FIG. 1, the left side isthe front end or front side, and the right side is the rear end or rearside.

First Embodiment

As shown in FIGS. 1, 2 and 3, the first embodiment of the presentdisclosure discloses an electric drive assembly with oil/water dualcooling comprising a motor module, a gearbox module, a water coolingmodule and an oil cooling module. The motor module comprises a motorhousing, a motor shaft and a stator 14, and the stator 14 is providedwith windings. The gearbox module comprises a gearbox housing 1, and thegearbox housing 1 is disposed at the rear end of the motor housing. Theconnection structure of the gearbox housing 1 and the motor housing isshown in FIG. 1 and FIG. 3.

The water cooling module in the present embodiment of the presentdisclosure mainly comprises a motor water jacket 12 and a heat exchanger3. The motor water jacket and the heat exchanger may be connectedtogether, or may be connected in series respectively. The motor waterjacket 12 may be integrally cast with the motor housing. Of course, itmay also be sleeved on the motor housing by assembly. The motor waterjacket 12 is provided with a first water inlet 10 and a first wateroutlet. The heat exchanger 3 is disposed at the lower end of the gearboxhousing 1. The heat exchanger 3 is provided with a second water inlet 19and a second water outlet 4. The motor water jacket 12 may be connectedwith the heat exchanger 3. For example, the cooling fluid in the motorwater jacket 12 is introduced into the heat exchanger 3 through a pipeor a passage provided in the gearbox housing 1. After circulation, thecooling fluid flows back to the vehicle reservoir through the secondwater outlet 4. Of course, the motor water jacket 12 and the heatexchanger 3 may also be connected to the vehicle reservoir through pipesrespectively.

The oil cooling module in the present embodiment of the presentdisclosure comprises an oil conveying device 2, an oil conveying passageand an oil return passage 16. The oil conveying device is disposed atthe bottom of the gearbox housing 1, the oil conveying passage iscommunicated with the inside of the motor housing and the inside of thegearbox housing 1, and the oil return passage 16 is disposed at thebottom of the motor housing. The oil conveying device 2 can lift, splashor spray the lubricating oil from the bottom of the gearbox housing 1,for example, it can send the lubricating oil to the first oil storagetank 21 and the second oil storage tank 22. The first oil storage tank21 and the second oil storage tank 22 are respectively communicated withthe first oil passage 11 and the second oil passage 6. The lubricatingoil in the oil storage tank is sent into the motor housing through theoil passages, so as to realize oil cooling and lubrication of the motor.The oil return passage 16 can return the lubricating oil into thegearbox housing 1, thereby realizing one circulation of lubricating oil.

Further, in an embodiment, the oil conveying device 2 is one or moregears, and/or the oil conveying device is one or more nozzles. The oilconveying device 2 may be one gear or a set of gears, and the rotationof the gear can splash the lubricating oil to realize oil conveying. Theoil conveying device 2 may also be a nozzle, which can be used to sprayoil into the oil passage or the oil storage tank. Of course, the oilconveying device may also be other devices that drive oil to move.

In a preferred embodiment, the oil conveying passage comprises a firstoil conveying passage. The first oil conveying passage comprises a firstoil storage tank 21, a first oil inlet, a first oil passage 11 and afirst oil outlet. The first oil inlet is disposed at the upper part ofthe front end face of the gearbox housing 1 above the motor housing. Thefirst oil storage tank 21 is disposed below the first oil inlet. Thefirst oil passage 11 is an oil pipe, or is cast integrally with themotor water jacket. The first oil passage 11 is provided with a firstoil outlet at the front end of the upper part of the motor housing, andpreferably, the first oil outlet is positioned facing the front winding13 of the stator 14.

Preferably, the first oil storage tank 21 is disposed on the inner wallof the front end face of the gearbox housing 1. The front end of thefirst oil storage tank 21 is connected to the first oil inlet. The firstoil storage tank 21 may extend to the rear end face of the gearboxhousing 1 through the side wall of the gearbox housing, so as toincrease the oil receiving area. Of course, it may not extend to therear end face of the gearbox housing 1. The first oil storage tank 21may be an integral structure with the gearbox housing 1, or may be acontainer such as a semicircular tube installed on the gearbox housing1. The lubricating oil in the oil storage tank enters the first oilpassage through the first oil inlet. The lubricating oil in the firstoil passage flows out of the first oil outlet due to gravity. The firstoil outlet is facing the front winding 13 to realize the cooling of thefront winding 13 by the lubricating oil.

In the present embodiment, the first oil passage 11 may be a built-inpassage formed on the motor housing by casting, or an external oil pipe.The oil pipe connection avoids the complicated oil passage structure onthe housing, reduces the casting difficulty of the housing, and isconvenient for layout on the whole vehicle.

In an embodiment, the oil conveying passage comprises a second oilconveying passage. The second oil conveying passage comprises a secondoil storage tank 22, a second oil inlet, a second oil passage 6 and asecond oil outlet. The second oil inlet is disposed at the lower part ofthe front end face of the gearbox housing 1 above the motor housing.Preferably, a second oil storage tank 22 is further provided. The secondoil storage tank 22 is disposed below the second oil inlet. The secondoil passage 6 is an oil pipe, or is formed by casting at theintersection of the front end of the gearbox housing and the rear end ofthe upper part of the motor housing. The second oil outlet is disposedat the rear end of the upper part of the motor housing, and preferably,the second oil outlet is positioned facing the rear winding 9 of themotor stator 14.

In the present embodiment, the second oil inlet is disposed below thefirst oil storage tank 21 and communicated with the second oil storagetank 22. The second oil storage tank 22 is disposed in parallel with thefirst oil storage tank 21, and the lubricating oil in the second oilstorage tank 22 flows into the second oil passage from the second oilinlet. Of course, in some cases, the second oil storage tank may not beprovided. Finally, the lubricating oil flows out of the second oiloutlet due to gravity and flows onto the rear winding 9, so as to coolthe rear winding 9 of the motor stator.

In the present embodiment, based on the same principle, the second oilpassage 6 may be a built-in passage formed on the motor housing bycasting, or an external oil pipe. The oil pipe connection avoids thecomplicated oil passage structure on the housing, reduces the castingdifficulty of the housing, and is convenient for layout on the wholevehicle.

In an embodiment, the oil conveying passage comprises a third oilconveying passage, and the third oil conveying passage is an oil passageformed by a rear end bearing 5 of the motor shaft. The third oilconveying passage is the passage for cooling and lubricating the rearend bearing of the motor shaft and the rear winding 9 of the stator.

Preferably, a strong magnetic body is provided at any one or more amongan oil inlet of the oil conveying passage, the bottom of the gearboxhousing 1 and the front side of the rear end bearing 5 of the motorshaft respectively. The purpose of providing the strong magnetic bodiesis to adsorb the iron filings in the lubricating oil, so as to purifythe lubricating oil and reduce the damage to the bearing.

In an embodiment, the water cooling module further comprises a waterpipe 18. The water pipe 18 is communicated with the first water outletand the second water inlet 19. The motor water jacket and heat exchanger3 are connected in series through the water pipe 18.

In an embodiment, a second water passage and a third water passage arefurther formed by casting in the housing between the motor water jacketand the heat exchanger 3. The second water passage is hermeticallyconnected or integrally formed with the second water inlet 19, and thethird water passage is hermetically connected or integrally formed withthe second water outlet 4. The cooling fluid in the motor water jacketflows into the heat exchanger 3 through the second water passage. Aftercooling the lubricating oil at the bottom of the gearbox housing 1, thecooling fluid flows back to the motor water jacket through the thirdwater passage. Finally, the cooling fluid flows to the vehicle reservoirthrough the water outlet at the upper part of the motor water jacket,thereby realizing one circulation of cooling fluid.

In an embodiment, the heat exchanger 3 and the gearbox housing 1 may becast integrally. Alternatively, the heat exchanger 3 may be regarded asa separate part and installed at the bottom of the gearbox housing 1.

To sum up, the present disclosure discloses an electric drive assemblywith oil/water dual cooling. The electric drive assembly comprises amotor module, a gearbox module, a water cooling module and an oilcooling module. The motor module comprises a motor housing, a motorshaft and a stator. The gearbox module comprises a gearbox housing, andthe gearbox housing is connected with a rear end of the motor housing.The water cooling module comprises a motor water jacket and a heatexchanger, the motor water jacket is integrally cast with the motorhousing, the motor water jacket is provided with a first water inlet anda first water outlet, the heat exchanger is disposed at a lower end ofthe gearbox housing, and the heat exchanger is provided with a secondwater inlet and a second water outlet. The oil cooling module comprisesan oil conveying device, an oil conveying passage and an oil returnpassage, the oil conveying device is disposed at a bottom of the gearboxhousing, the oil conveying passage is communicated with an inside of themotor housing and an inside of the gearbox housing, and the oil returnpassage is disposed at a bottom of the motor housing. In this technicalsolution, the lubricating oil is introduced onto the front and rearwindings of the motor through three oil conveying passages, the coolingperformance of the motor is improved; moreover, the gearbox cavity andthe motor cavity do not need to be sealed, which avoids the use ofhigh-speed oil seal of motor shaft, and thus the cost of the driveassembly is reduced and the transmission efficiency is improved. Thecooling fluid of the motor cools the lubricating oil through the heatexchanger of the gearbox, thereby solving the heat dissipation problemwhen the gearbox of the new energy vehicle operates under a high speedconstantly, and thus improving the service life and reliability of thegear and bearing.

Second Embodiment

The present embodiment of the present disclosure also discloses a newenergy vehicle comprising any one of the electric drive assemblies withoil/water dual cooling as stated above.

The above are only the specific embodiments of the present disclosure,but the protection scope of the present disclosure is not limited tothis. Any person skilled in the art can easily think of changes orsubstitutions within the technical scope disclosed by the presentdisclosure, which should be covered by the protection scope of thepresent disclosure. Therefore, the protection scope of the presentdisclosure shall be subject to the protection scope of the claims.

1. An electric drive assembly with oil/water dual cooling, the electricdrive assembly comprising: a motor module having a motor housing, amotor shaft and a stator; a gearbox module having a gearbox housing, andthe gearbox housing is connected with a rear end of the motor housing; awater cooling module having a motor water jacket and a heat exchanger,the motor water jacket is integrally cast with the motor housing, themotor water jacket is provided with a first water inlet and a firstwater outlet, the heat exchanger is disposed at a lower end of thegearbox housing, and the heat exchanger is provided with a second waterinlet and a second water outlet; and an oil cooling module having an oilconveying device, an oil conveying passage and an oil return passage,the oil conveying device is disposed at a bottom of the gearbox housing,the oil conveying passage is communicated with an inside of the motorhousing and an inside of the gearbox housing, and the oil return passageis disposed at a bottom of the motor housing.
 2. The electric driveassembly according to claim 1, wherein the oil conveying device is atleast one of one or more gears and one or more nozzles.
 3. The electricdrive assembly according to claim 1, wherein the oil conveying passagecomprises a first oil conveying passage, and the first oil conveyingpassage comprises a first oil storage tank, a first oil inlet, a firstoil passage and a first oil outlet; the first oil inlet is disposed onan upper part of a front end face of the gearbox housing above the motorhousing, the first oil storage tank is disposed below the first oilinlet, the first oil passage is an oil pipe or is cast integrally withthe motor water jacket, the first oil passage is provided with a firstoil outlet at a front end of an upper part of the motor housing, and thefirst oil outlet is positioned facing a front winding of the stator. 4.The electric drive assembly according to claim 1, wherein the oilconveying passage comprises a second oil conveying passage, and thesecond oil conveying passage comprises a second oil storage tank, asecond oil inlet, a second oil passage and a second oil outlet; thesecond oil inlet is disposed at a position on the front end face of thegearbox housing above the motor housing that is close to the motorhousing, the second oil storage tank is disposed below the second oilinlet, the second oil passage is an oil pipe, or is formed by casting atan intersection of a front end of the gearbox housing and an upper partof the motor housing, the second oil outlet is disposed at a rear end ofthe upper part of the motor housing, and the second oil outlet ispositioned facing a rear winding of the motor stator.
 5. The electricdrive assembly according to claim 1, wherein the oil conveying passagecomprises a third oil conveying passage, and the third oil conveyingpassage is an oil passage formed by a rear end bearing of the motorshaft.
 6. The electric drive assembly according to claim 1, wherein astrong magnetic body is provided at any one or more among an oil inletof the oil conveying passage, the bottom of the gearbox housing and afront side of a rear end bearing of the motor shaft respectively.
 7. Theelectric drive assembly according to claim 1, wherein the water coolingassembly further comprises a water pipe, and the first water outlet andthe second water inlet are communicated through the water pipe.
 8. Theelectric drive assembly according to claim 1, wherein a second waterpassage and a third water passage are further formed by casting in ahousing between the motor water jacket and the heat exchanger, thesecond water passage is hermetically connected or integrally formed withthe second water inlet, and the third water passage is hermeticallyconnected or integrally formed with the second water outlet.
 9. Theelectric drive assembly according to claim 1, wherein the heat exchangerand the gearbox housing are integrally cast, or the heat exchanger isinstalled at the bottom of the gearbox housing.
 10. A new energyvehicle, comprising an electric drive assembly with oil/water dualcooling according to claim
 1. 11. The new energy vehicle according toclaim 10, wherein the oil conveying device is at least one of one ormore gears and one or more nozzles.
 12. The new energy vehicle accordingto claim 10, wherein the oil conveying passage comprises a first oilconveying passage, and the first oil conveying passage comprises a firstoil storage tank, a first oil inlet, a first oil passage and a first oiloutlet, and wherein the first oil inlet is disposed on an upper part ofa front end face of the gearbox housing above the motor housing, thefirst oil storage tank is disposed below the first oil inlet, the firstoil passage is an oil pipe or is cast integrally with the motor waterjacket, the first oil passage is provided with a first oil outlet at afront end of an upper part of the motor housing, and the first oiloutlet is positioned facing a front winding of the stator.
 13. The newenergy vehicle according to claim 10, wherein the oil conveying passagecomprises a second oil conveying passage, and the second oil conveyingpassage comprises a second oil storage tank, a second oil inlet, asecond oil passage and a second oil outlet, and wherein the second oilinlet is disposed at a position on the front end face of the gearboxhousing above the motor housing that is close to the motor housing, thesecond oil storage tank is disposed below the second oil inlet, thesecond oil passage is an oil pipe, or is formed by casting at anintersection of a front end of the gearbox housing and an upper part ofthe motor housing, the second oil outlet is disposed at a rear end ofthe upper part of the motor housing, and the second oil outlet ispositioned facing a rear winding of the motor stator.
 14. The new energyvehicle according to claim 10, wherein the oil conveying passagecomprises a third oil conveying passage, and the third oil conveyingpassage is an oil passage formed by a rear end bearing of the motorshaft.
 15. The new energy vehicle according to claim 10, wherein astrong magnetic body is provided at any one or more among an oil inletof the oil conveying passage, the bottom of the gearbox housing and afront side of a rear end bearing of the motor shaft respectively. 16.The new energy vehicle according to claim 10, wherein the water coolingassembly further comprises a water pipe, and the first water outlet andthe second water inlet are communicated through the water pipe.
 17. Thenew energy vehicle according to claim 10, wherein a second water passageand a third water passage are further formed by casting in a housingbetween the motor water jacket and the heat exchanger, the second waterpassage is hermetically connected or integrally formed with the secondwater inlet, and the third water passage is hermetically connected orintegrally formed with the second water outlet.
 18. The new energyvehicle according to claim 10, wherein the heat exchanger and thegearbox housing are integrally cast, or the heat exchanger is installedat the bottom of the gearbox housing.